Roughly tare the leftover chapati/roti into pieces and add them to the blender. Using pulse mode grind them to small bite-size pieces as shown below. Do not make powder of it.
Heat 2 tablespoons oil in a pan. Add mustard seeds and let them crackle. Now add cumin seeds and let them sizzle for one minute.
Add 1/4th teaspoon hing (asafoetida) and 1/2 teaspoon turmeric powder.
Add greed chillies, curry leaves and finely chopped onions. Cook onions till they are translucent. Keep the flame low to medium.
Once the onions are cooked add the ground poli/chapati/roti . At this point keep the flame low. Mix the chapati well with the onion mixture.
Add salt and sugar, and mix well till masala is nicely incorporated into the chapati mixture. Check seasoning at this time.
Cover the pan with a lid and let the poli/roti get nice steam for about 5-7 minutes on low flame so that the poli softens up.
Stir occasionally to avoid the mixture sticking to the bottom of the pan.
Lastly add freshly chopped coriander leaves and a tablespoon of coconut(optional).
Maharashtrian Style Phodnichi Poli is ready.
Garnish with finely chopped coriander leaves and serve hot.